LOG // ENGINEER'S LOG

Engineer's Log

Write-ups from my projects, including the parts that broke and what the numbers showed.

FILED UNDER: #arduino · #build-log · #controls · #deep-learning · #elm · #functional-programming · #games · #hardware · #machine-learning · #methodology · #numpy · #postmortem

3 MIN READ

Trust, but Verify: Checking Backprop to 1e-16

How I checked my hand-derived gradients against PyTorch autograd before training anything on CIFAR-10, and why overfitting a tiny subset catches bugs that a gradient check misses.

  • #machine-learning
  • #numpy
  • #deep-learning
  • #methodology
3 MIN READ

Levitation Is a Control Problem

Build log from the maglev platform. Why magnetic levitation is unstable, and how a Hall-effect sensor, some op-amps and an Arduino pretending to be a PWM chip keep a platform floating.

  • #hardware
  • #controls
  • #arduino
  • #build-log
3 MIN READ

Shipping a Game in a Language With No Exceptions

Postmortem for GhostBust Hotline. What it was like to lead a team of three building a real-time shooter in Elm, a pure functional language, and why the compiler ended up helping us so much.

  • #games
  • #elm
  • #functional-programming
  • #postmortem